1. Field of the Invention
This invention pertains to new condensation products of derivatives of Meldrum's acid with N-alkyl-1,3-propanediamines and to a method for making same.
2. Overview of the Technology
Meldrum's acid was previously known as the B-lactone of B-hydroxyisopropylmalonic acid and its preparation given in CA 2:1421.sup.7. Its correct structure was reported in JACS 70, 3246-8 (1948) as isopropylidene malonate (2,2-dimethyl-4,6-diketo-1,3-dioxane). The reaction of this compound with liquid ammonia followed by the evaporation of the ammonia is said in CA 55:22,125.sup.d as yielding its ammonium salt, of unstated utility. The same reference mentions the reaction of Meldrum's acid with benzenediazonium sulfonate in dilute aqueous Na.sub.2 CO.sub.3 neutralized with acetic acid as yielding 2,2-dimethyl-1,3-dioxane-4,5,6-trione 5-phenylhydrazone, of unstated utility.
As regards the other reactant used with the present invention, certain N-alkyl-alkylene diamine compounds, as represented by N-oleyl-1,3-diaminopropane, are known to give carburetor detergency properties to gasoline. These additives, however, do not impart corrosion inhibiting properties to gasoline. As a result, a motor fuel containing an N-alkyl-alkylene diamine must be modified or formulated with an additional additive in order to have the necessary corrosion inhibiting properties for marketability.
The known art in no way suggest the reaction of Meldrum's acid-type compounds with N-alkyl-1,3-propanediamines to form compounds useful as carburetor detergents and corrosion inhibitors in gasoline fuels.